The process of authentication has particular application in any system (chip or software) that manipulates secure data. This includes Internet commerce, peer to peer communication, Smart Cards, Authentication chips, electronic keys, and cryptographic equipment. Whilst the description of the preferred embodiments of the present invention assumes a System/consumable relationship, it is a trivial matter to extend the protocol for other uses. An example is Internet commerce, where each consumer is effectively the consumable, and the Shop is the System. Another usage is Smart Cards, where each smart card can have a unique key, known to the System.
Existing solutions to the problem of authenticating consumables have typically relied on physical patents on packaging. However this does not stop inferior refill operations or clone manufacture in countries with weak industrial property protection. Consequently a much higher level of protection is required.